A landing gear turning angle measuring tool

Abstract

The present application relates to a measuring tool which can accurately measure the turning angle of various types of landing gears. The tool comprises a base plate assembly, a rotating disc assembly and a driving block assembly. The base plate assembly comprises a mounting portion A and a sliding groove portion. The mounting portion A is used to mount the base plate assembly to a piston rod. The sliding groove portion is arranged at one end of the mounting portion A and is provided with a sliding groove and a scale A. The rotating disc assembly comprises a sliding portion and a limiting portion B. The sliding portion is adapted to the sliding groove and can slide along the extension direction of the sliding groove. The sliding portion is provided with a scale B. The limiting portion B is arranged at one side of the sliding portion. The driving block assembly comprises a mounting portion C and a limiting portion C. The mounting portion C is used to mount the driving block assembly to an outer cylinder. The limiting portion C is arranged at one end of the mounting portion C and cooperates with the limiting portion B. The present application has the following advantages: the turning angle can be accurately measured; the tool structure is exquisite, simple and convenient to use and has good compatibility.

Description

Technical Field

[0001] This invention relates to a measuring fixture that can accurately measure the turning angle of various types of landing gear. Background Technology

[0002] To meet the requirements of ground taxiing performance, most aircraft are equipped with a nose wheel steering system to achieve directional control during taxiing. Therefore, the nose landing gear generally has a steering function, and the turning angle of the landing gear is one of the important indicators for measuring the turning function.

[0003] To measure the landing gear camber angle, the traditional method involves using a large jig to fix the landing gear in place. An angle dial is designed in the center of the jig, and a pointer is fixed to the landing gear piston rod and aligned with the zero position on the dial. The landing gear is then rotated to its extreme positions on both sides, and the angle indicated by the pointer at each extreme position is recorded to obtain the landing gear camber angle parameter. However, this measurement method has the following drawbacks: 1. Due to the relatively complex structure and heavy weight of the landing gear, it is difficult and time-consuming to install it on a large frame. 2. When the landing gear is installed on a large frame, it is difficult to ensure that the center of rotation of the landing gear coincides with the center of the angle dial, resulting in low measurement accuracy. This is not suitable for some models that require high accuracy in turning angles. 3. Since most domestic landing gear uses cylindrical cams as the components to achieve the centering function, the landing gear will inevitably contract during the turning process due to the fitting effect of the cam profile, causing the pointer to gradually move away from the dial as it rotates, further affecting the measurement accuracy. 4. Because the landing gear interface dimensions are different, a single template can often only measure the landing gear turning angle of one aircraft model. Producing multiple landing gear models requires customizing multiple templates, resulting in higher production costs. Summary of the Invention

[0004] The purpose of this invention is to provide a landing gear turning angle measuring fixture to achieve accurate, efficient, and low-cost measurement of the landing gear turning angle.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a landing gear turning angle measuring fixture, comprising a base plate assembly, a rotating disk assembly, and a drive block assembly; The base plate assembly includes a mounting part A and a sliding part. The mounting part A is used to mount the base plate assembly onto the piston rod. The sliding part is located at one end of the mounting part A and is provided with a sliding groove and a scale A. The rotating disk assembly includes a sliding part and a limiting part B. The sliding part is adapted to the slide groove and can slide along the extension direction of the slide groove. It is provided with a scale B. The limiting part B is provided on one side of the sliding part. The drive block assembly includes a mounting part C and a limiting part C. The mounting part C is used to mount the drive block assembly onto the outer cylinder. The limiting part C is located at one end of the mounting part C and cooperates with the limiting part B. When the outer cylinder is fixed and the piston rod is rotated to the limit position, the limiting part B is limited by the limiting part C and remains stationary. The slide groove slides relative to the sliding part, thereby reading the change in angle through the scale.

[0006] Preferably, the slide is an annular groove with a T-shaped cross-section, and the scale A is set on the side of the slide; the other side of the sliding part is a T-shaped boss, which is embedded in the slide.

[0007] Preferably, the mounting part A includes a base plate and a base plate pressing block, which are arranged opposite to each other. One end of the base plate is fixed to the sliding groove and the other end is a free end. One end of the base plate pressing block is rotatably connected to the sliding groove and the other end is a free end. The mounting part C includes a driving block and a driving block pressing plate, which are arranged opposite to each other. One end of the driving block is fixed to the limiting part C and the other end is a free end. One end of the driving block pressing plate is rotatably connected to the limiting part C and the other end is a free end.

[0008] Preferably, the limiting part B is a limiting shaft, and the limiting part C is a U-shaped groove, with the outer diameter of the limiting shaft being smaller than the inner diameter of the U-shaped groove; after the measuring fixture is installed, the end of the limiting shaft extends into the U-shaped groove for limiting.

[0009] Furthermore, it also includes a reset pin, which is inserted into a through hole opened at the corresponding position of the sliding part and the sliding groove part to complete the angle zeroing, and the center of the through hole is opposite to the zero position of scale A and scale B.

[0010] Preferably, the through hole is a tapered hole.

[0011] Preferably, protective plates are provided on the inner sides of both mounting parts A and C, which are used to adjust the relative positions of the base plate assembly relative to the center of the piston rod and the drive block assembly relative to the center of the outer cylinder, respectively.

[0012] Preferably, both mounting part A and mounting part C are V-shaped block structures.

[0013] Preferably, the mounting part A includes a standard inner diameter clamp and a quick-change interface. The standard inner diameter clamp is connected and fixed to the piston rod, and the quick-change interface is connected and fixed to the slide groove part.

[0014] Instructions for use: First, install the base plate assembly on the piston rod. The rotating disk assembly is in movable engagement with the base plate assembly through the built-in precision T-slot. Then, install the drive block assembly on the outer cylinder and fix the outer cylinder in place (any fixing method is acceptable; you can use felt and a vise to fix it). Adjust the rotating disk assembly to zero and you can start rotating the landing gear. You can directly read the reading on the rotating disk assembly to obtain the measured turning angle.

[0015] Compared with the prior art, the present invention has the following advantages: the precision groove on the drive block assembly and the precision shaft on the rotary disk assembly cooperate to form a guide rail slider structure, which can accurately transmit the turning angle variable without changing the longitudinal position of the piston rod. In conjunction with the scale on the rotary disk assembly and the base plate assembly, the turning angle can be accurately measured. The tooling structure is ingenious and can directly connect to the piston rod and the outer circle of the outer cylinder without avoiding other features on the landing gear. It can be applied to the turning angle measurement of multiple landing gear models, and is simple, convenient and compatible to use. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the working state of an embodiment of the present invention (a, turning angle measuring fixture; b, landing gear with the angle to be measured). Figure 2 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 3 These are schematic diagrams of the assembled structure of an embodiment of the present invention (a, side view; b, top view; c, AA view). Figure 4 This is a schematic diagram of the usage steps in an embodiment of the present invention (step 1); Figure 5 This is a schematic diagram of the usage steps in an embodiment of the present invention (step 2); Figure 6 This is a schematic diagram of the usage steps in an embodiment of the present invention (step 3); Figure 7 This is a schematic diagram of the usage steps in an embodiment of the present invention (step 4); Figure 8 This is a schematic diagram of the improved structure of the base plate assembly in an embodiment of the present invention; Figure 1 In the middle, 1-drive block assembly; 2-base plate assembly; 3-reset pin; 4-rotary disk assembly; 5-piston rod; 6-outer cylinder; Figure 2 In the middle, 1.1-earring bolt; 1.2-tightening nut; 1.3-drive block; 1.4-drive block pressure plate; 2.1-tightening nut; 2.2-earring bolt; 2.3-base plate; 2.4-base plate pressure plate; Figure 8 In the middle, 7. Base chuck; 8. Quick-change interface; 9. Standard inner diameter clamp. Detailed Implementation

[0017] The following is in conjunction with the appendix Figure 1-8The present invention is further described in detail as follows: A landing gear turning angle measuring fixture mainly consists of a base plate assembly 2, a rotating disk assembly 4 and a drive block assembly 1, wherein the base plate assembly 2 and the drive block assembly 1 are respectively pre-tightly connected to the piston rod and the outer cylinder through a V-shaped block structure, the rotating disk assembly 4 cooperates with the base plate through an annular precision T-groove, and the reset pin 3 passes through the rotating disk assembly 4 and the base plate assembly 2 through a conical hole.

[0018] like Figure 1-3 As shown, the base plate assembly 2 consists of a tightening nut 2.1, an ear bolt 2.2, a base plate 2.3, and a base plate pressure plate 2.4. The base plate 2.3 and the base plate pressure plate 2.4 are arranged opposite to each other. One end of the base plate 2.3 is fixed to the sliding groove, and the other end is a free end with a U-shaped groove. The opening end of the U-shaped groove is located at this end. Both ends of the base plate pressure plate 2.4 are provided with through holes. One end of the through hole is rotatably connected to the sliding groove through a pin, and the other end is a free end. The base plate assembly 2 is fixed to the circumference of the piston rod by the tightening nut 2.1 and the ear bolt 2.2 installed on the U-shaped groove and the through hole. The T-shaped precision annular groove on the base plate 2.3 restricts the rotating disk assembly 4 to only make circular motion along the annular groove. The structure of the V-shaped block ensures that after the piston rod is installed, the center of motion of the piston rod must be on the center of symmetry of the V-shaped block. By replacing the built-in protective plate according to the different outer diameter of the piston rod, it can be ensured that the center of the piston rod coincides with the center of the base plate assembly 2 and the rotating disk assembly 4, thereby ensuring the accurate measurement of the turning angle. like Figure 1-3 As shown, the rotating disk assembly 4 includes a rotating disk, a T-shaped boss, and an extended shaft. The T-shaped boss and the extended shaft are respectively arranged on opposite sides of the rotating disk. The rotating disk is guided by the annular precision T-shaped boss in conjunction with the base plate assembly 2, and the angle change is converted into circumferential motion through the annular groove. The angle change is then read by the angle value scale markings on the rotating disk and the base plate assembly. like Figure 1-3 As shown, the drive block assembly 1 mainly consists of an ear bolt 1.1, a tightening nut 1.2, a drive block 1.3, and a drive block pressure plate 1.4. The precision groove on the drive block assembly 1 engages with the precision extended shaft on the rotating disk. Using a slider-like mechanism, the rotational variable of the outer cylinder relative to the piston is transmitted to the rotating disk, while simultaneously allowing the axial movement of the rotating disk to be unrestricted. Figure 4-7 As shown, even though the cam structure traction landing gear retracts synchronously during rotation, it does not affect the angle measurement results at all.

[0019] This fixture converts the change in piston rod angle into the circular motion of a rotating disk through the V-shaped block and T-shaped precision annular groove structure on the base plate assembly 2. Then, the change in the rotation angle of the landing gear is transmitted through the slider-like mechanism of the drive block assembly 1 and the rotating disk assembly. Finally, the measurement result of the turning angle is obtained intuitively through the scale values ​​on the rotating disk and the base plate.

[0020] like Figure 4-7 As shown, the tooling is used as follows: 1. Calibration before measurement: Pre-tighten the base plate assembly 2 (with the rotating disk already installed on the base plate) onto the piston rod 5, and pre-tighten the drive block assembly 1 onto the outer cylinder 6. Then insert the reset pin 3 to zero the scale, and lock the base plate assembly 2 and drive block assembly 1 in sequence. 2. Angle measurement: Fix the outer cylinder 6 (the fixing method can be chosen freely, such as using wool felt and vise to fix it), pull out the reset pin 3, rotate the piston rod 5 to the extreme positions in two directions respectively, and directly read the reading on the rotating disk to obtain the measured turning angle.

[0021] The positional accuracy requirement of the drive block assembly 1 relative to the outer cylinder is not high, and the inner side is covered with a protective plate, which can withstand a certain degree of forced assembly and simplifies the tooling installation process; the relative position of the piston rod center can be adjusted by replacing the protective plate on the inner side of the base plate assembly. The reset pin 3, combined with the tapered hole design, can accurately complete the angle zeroing process, further improving measurement efficiency; The base plate assembly uses a V-block structure to ensure high compatibility under proper adjustment and measurement. Alternatively, it can also use... Figure 8 The structure shown has been improved so that the base plate assembly is a structure in which the base chuck 7 and the standard inner diameter clamp 9 and quick-change interface 8 are matched. When using it, the appropriate clamp is selected according to the size of the piston rod outer diameter, which can also save the time of checking the rotation center.

[0022] This tooling can avoid external structural components such as torque arms and earrings, and will not interfere at all during the opening and closing process, making it widely applicable.

Claims

1. A fixture for measuring the turning angle of landing gear, characterized in that: Includes base plate assembly, rotating disk assembly, and drive block assembly; The base plate assembly includes a mounting part A and a sliding part. The mounting part A is used to mount the base plate assembly onto the piston rod. The sliding part is located at one end of the mounting part A and is provided with a sliding groove and a scale A. The rotating disk assembly includes a sliding part and a limiting part B. The sliding part is adapted to the slide groove and can slide along the extension direction of the slide groove. It is provided with a scale B. The limiting part B is provided on one side of the sliding part. The drive block assembly includes a mounting part C and a limiting part C. The mounting part C is used to mount the drive block assembly onto the outer cylinder. The limiting part C is located at one end of the mounting part C and cooperates with the limiting part B. When the outer cylinder is fixed and the piston rod is rotated to the limit position, the limiting part B is limited by the limiting part C and remains stationary. The slide groove slides relative to the sliding part, thereby reading the change in angle through the scale.

2. The landing gear turning angle measuring fixture according to claim 1, characterized in that: The slide is an annular groove with a T-shaped cross-section, and the scale A is set on the side of the slide; the other side of the sliding part is a T-shaped boss, which is embedded in the slide.

3. The landing gear turning angle measuring fixture according to claim 1, characterized in that: Mounting part A includes a base plate and a base plate pressing block, which are arranged opposite to each other. One end of the base plate is fixed to the sliding groove, and the other end is a free end. One end of the base plate pressing block is rotatably connected to the sliding groove, and the other end is a free end. Mounting part C includes a driving block and a driving block pressing plate, which are arranged opposite to each other. One end of the driving block is fixed to the limiting part C, and the other end is a free end. One end of the driving block pressing plate is rotatably connected to the limiting part C, and the other end is a free end.

4. The landing gear turning angle measuring fixture according to claim 1, characterized in that: Limiting part B is a limiting shaft, and limiting part C is a U-shaped groove. The outer diameter of the limiting shaft is smaller than the inner diameter of the U-shaped groove. After the measuring fixture is installed, the end of the limiting shaft extends into the U-shaped groove for limiting.

5. The landing gear turning angle measuring fixture according to claim 1, characterized in that: It also includes a reset pin, which is inserted into the through hole opened at the corresponding position of the sliding part and the sliding groove part to complete the angle zeroing, and the center of the through hole is opposite to the zero position of scale A and scale B.

6. The landing gear turning angle measuring fixture according to claim 5, characterized in that: The through hole is a tapered hole.

7. The landing gear turning angle measuring fixture according to claim 1, characterized in that: Protective plates are provided on the inner sides of both mounting sections A and C, which are used to adjust the relative positions of the base plate assembly relative to the center of the piston rod and the drive block assembly relative to the center of the outer cylinder, respectively.

8. The landing gear turning angle measuring fixture according to claim 7, characterized in that: Both mounting section A and mounting section C are V-shaped block structures.

9. The landing gear turning angle measuring fixture according to claim 1, characterized in that: Mounting section A includes a standard inner diameter clamp and a quick-change interface. The standard inner diameter clamp is connected and fixed to the piston rod, and the quick-change interface is connected and fixed to the slide section.

Images